e period
of time, it being necessary to remove the thermometer only for
defecation.

As a result of these observations it was soon found that the body
temperature was not constant from hour to hour, but fluctuated
considerably and underwent more or less regular rhythm with the minimum
between 3 and 5 o'clock in the morning and the maximum about 5 o'clock
in the afternoon. In a number of experiments where the mercurial
thermometer was used under the tongue and observations thus taken
compared with records with the resistance thermometer, it was found that
with careful manipulation and avoiding muscular activity, mouth
breathing, and the drinking of hot or cold liquid, a fairly uniform
agreement between the two could be obtained. Such comparisons made on
laboratory assistants can not be duplicated with the ordinary subject.

It is assumed that fluctuations in temperature measured by the rectal
thermometer likewise hold true for the average temperature of the whole
body, but evidence on this point is unfortunately not as complete as is
desirable. In an earlier report of investigations of this nature, a few
experiments on comparison of measurements of resistance thermometer deep
in the rectum and in a well-closed axilla showed a distinct tendency for
the curves to continue parallel. A research is very much needed at
present on a topographical distribution of body temperature, and
particularly on the course of the fluctuations in different parts of the
body. A series of electric-resistance thermometers placed at different
points in the colon, at different points in a stomach tube, in the
well-closed axilla, possibly attached to the surface of the body, and in
women in the vagina, should give a very accurate picture of the
distribution of the body-temperature and likewise indicate the
proportionality of the fluctuations in different parts of the body.
Until such a research is completed, however, it is necessary to assume
that fluctuations in body-temperature as measured by the electric rectal
thermometer are a true measure of the average body-temperature of the
whole body. Indeed it is upon this assumption that it is necessary for
us to make corrections for heat lost from or stored in the body. It is
our custom, therefore, to compute the hydrothermal equivalent by
multiplying the body-weight by the specific heat of the body, commonly
assumed as 0.83, and then to make allowance for fluctuations in
body-temperature.

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